parse.c revision 1.8 
1/*	$NetBSD: parse.c,v 1.8 2000/09/21 17:44:34 jsm Exp $	*/
2
3/*
4 * Copyright (c) 1983, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *	This product includes software developed by the University of
18 *	California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36#include <sys/cdefs.h>
37#ifndef lint
38#if 0
39static char sccsid[] = "@(#)parse.c	8.2 (Berkeley) 4/28/95";
40#else
41__RCSID("$NetBSD: parse.c,v 1.8 2000/09/21 17:44:34 jsm Exp $");
42#endif
43#endif				/* not lint */
44
45#include "extern.h"
46
47void
48wordinit()
49{
50	struct wlist *w;
51
52	for (w = wlist; w->string; w++)
53		install(w);
54}
55
56int
57hash(s)
58	const char   *s;
59{
60	int     hashval = 0;
61
62	while (*s) {
63		hashval += *s++;
64		hashval *= HASHMUL;
65		hashval &= HASHMASK;
66	}
67	return hashval;
68}
69
70struct wlist *
71lookup(s)
72	const char   *s;
73{
74	struct wlist *wp;
75
76	for (wp = hashtab[hash(s)]; wp != NULL; wp = wp->next)
77		if (*s == *wp->string && strcmp(s, wp->string) == 0)
78			return wp;
79	return NULL;
80}
81
82void
83install(wp)
84	struct wlist *wp;
85{
86	int     hashval;
87
88	if (lookup(wp->string) == NULL) {
89		hashval = hash(wp->string);
90		wp->next = hashtab[hashval];
91		hashtab[hashval] = wp;
92	} else
93		printf("Multiply defined %s.\n", wp->string);
94}
95
96void
97parse()
98{
99	struct wlist *wp;
100	int     n;
101	int     flag;
102
103	wordnumber = 0;		/* for cypher */
104	for (n = 0; n <= wordcount; n++) {
105		if ((wp = lookup(words[n])) == NULL) {
106			wordvalue[n] = -1;
107			wordtype[n] = -1;
108		} else {
109			wordvalue[n] = wp->value;
110			wordtype[n] = wp->article;
111		}
112	}
113	/* Don't let a comma mean AND if followed by a verb. */
114	for (n = 0; n < wordcount; n++)
115		if (wordvalue[n] == AND && words[n][0] == ','
116		    && wordtype[n + 1] == VERB) {
117			wordvalue[n] = -1;
118			wordtype[n] = -1;
119		}
120	/* Trim "AND AND" which can happen naturally at the end of a
121	 * comma-delimited list.
122	 */
123	for (n = 1; n < wordcount; n++)
124		if (wordvalue[n - 1] == AND && wordvalue[n] == AND) {
125			int i;
126			for (i = n + 1; i < wordcount; i++) {
127				wordtype[i - 1] = wordtype[i];
128				wordvalue[i - 1] = wordvalue[i];
129				strcpy(words[i - 1], words[i]);
130			}
131			wordcount--;
132		}
133
134	/* If there is a sequence (NOUN | OBJECT) AND EVERYTHING
135	 * then move all the EVERYTHINGs to the beginning, since that's where
136	 * they're expected.  We can't get rid of the NOUNs and OBJECTs in
137	 * case they aren't in EVERYTHING (i.e. not here or nonexistant).
138	 */
139	flag = 1;
140	while (flag) {
141		flag = 0;
142		for (n = 1; n < wordcount; n++)
143			if ((wordtype[n - 1] == NOUNS || wordtype[n - 1] == OBJECT) &&
144			    wordvalue[n] == AND && wordvalue[n + 1] == EVERYTHING) {
145				char tmpword[WORDLEN];
146				wordvalue[n + 1] = wordvalue[n - 1];
147				wordvalue[n - 1] = EVERYTHING;
148				wordtype[n + 1] = wordtype[n - 1];
149				wordtype[n - 1] = OBJECT;
150				strcpy(tmpword, words[n - 1]);
151				strcpy(words[n - 1], words[n + 1]);
152				strcpy(words[n + 1], tmpword);
153				flag = 1;
154		}
155		/* And trim EVERYTHING AND EVERYTHING. */
156		for (n = 1; n < wordcount; n++)
157			if (wordvalue[n - 1] == EVERYTHING &&
158			    wordvalue[n] == AND && wordvalue[n + 1] == EVERYTHING) {
159				int i;
160				for (i = n + 1; i < wordcount; i++) {
161					wordtype[i - 1] = wordtype[i + 1];
162					wordvalue[i - 1] = wordvalue[i + 1];
163					strcpy(words[i - 1], words[i + 1]);
164				}
165				wordcount--;
166				wordcount--;
167				flag = 1;
168			}
169	}
170}
171